I thought it would do that sometime.That vortech chip was made for a bone stock car.I didnt think they did anything to it.Better call TJ and tell him bout it.Most likely you will need a custom chip for what you have.Vortech told us not to put any pipes and what not on my car for the fear that it would throw a check engine light.So if that light keeps coming on that means the computer is going into safe mode so your losing power.Just stay out of the pedal for awhile.Dont want to make the thing start pinging.Looks like your gonna need a dyno tune chip now.Which would give you way more power anyways.But yeah no check light for me for my car still has the stock cats in it.The 99 ups are real picky with aftermarket cat pipes.Either it will not throw a light or it will.